知识是人类所创造的宝贵财富，但至今没有形成系统的知识理论。文章旨在提出和建立知识论的框架体系，包括它的基础和主体两部分。基础部分主要给出知识的概念、定义、表示、度量、推理和决策规则；主体部分的核心是阐明由信息提炼知识（知识生成）以及由知识形成智能（知识激活）的机理。知识论的建立将为信息论-知识论-智能论的统一理论奠定坚实的基础，促进人们在更高的水平上利用信息和知识，研究、设计和应用各种智能机器，推动经济和社会的发展。

Knowledge has been very important wealth to the mankind but there has not a knowledge theory existed yet till the present time. An attempt is thus made in the paper to present a framework of knowledge theory that includes two parts: fundamentals and the main body of knowledge theory. The first part is to deal with a series of basic issues such as the related concepts and definitions, the methods of representation, the measurements, the reasoning and decision rules. The second part is to explore the mechanism of knowledge formation based on information processing and the mechanism of intelligence formation based on the activation of knowledge. It is believed that the establishment of the knowledge theory will lay a solid foundation to the unified theory of information, knowledge, and intelligence and will greatly facilitate the effective utilization of information and knowledge, leading to the growth of the research in the field of intelligent machines.